ValueError: Only one class present in y_true. ROC AUC score is not defined in that case. about resdsql

[lihaoyang-ruc]

这个报错来自AUC指标，当输入的labels全是0或者全是1的时候，就会报这个错误。

>>> from sklearn.metrics import roc_auc_score
>>> roc_auc_score([0,0,0], [0.1, 0.1, 0.2])
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/home/haoyang/anaconda3/envs/python38/lib/python3.8/site-packages/sklearn/metrics/_ranking.py", line 572, in roc_auc_score
    return _average_binary_score(
  File "/home/haoyang/anaconda3/envs/python38/lib/python3.8/site-packages/sklearn/metrics/_base.py", line 75, in _average_binary_score
    return binary_metric(y_true, y_score, sample_weight=sample_weight)
  File "/home/haoyang/anaconda3/envs/python38/lib/python3.8/site-packages/sklearn/metrics/_ranking.py", line 339, in _binary_roc_auc_score
    raise ValueError(
ValueError: Only one class present in y_true. ROC AUC score is not defined in that case.
>>> roc_auc_score([1,1,1], [0.1, 0.1, 0.2])
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/home/haoyang/anaconda3/envs/python38/lib/python3.8/site-packages/sklearn/metrics/_ranking.py", line 572, in roc_auc_score
    return _average_binary_score(
  File "/home/haoyang/anaconda3/envs/python38/lib/python3.8/site-packages/sklearn/metrics/_base.py", line 75, in _average_binary_score
    return binary_metric(y_true, y_score, sample_weight=sample_weight)
  File "/home/haoyang/anaconda3/envs/python38/lib/python3.8/site-packages/sklearn/metrics/_ranking.py", line 339, in _binary_roc_auc_score
    raise ValueError(
ValueError: Only one class present in y_true. ROC AUC score is not defined in that case.
>>> roc_auc_score([1,0,1], [0.1, 0.1, 0.2])
0.75

不过我一时想不到很好的解决办法，你可以简单地加个try except来捕捉它。

[CyanMystery]

好的。谢谢~